asp.net application + single sign on

I want to implement single sign on in my asp.net web application. Scenario is something like below:

1. user will get registered / sign 开发者_如何学JAVAup at "account.example.com"
2. there will a link to "professional.example.com"
3. when user goes to this link (step 2), they must remain logged in over here.

What is the best solution for this?

You want to set the Domain property on the cookie object to ".example.com" and it will work for any sub-domain of "example.com".

If you're using ASP.NET's forms authentication, this article is a good place to start to find out all the options for configuring it.

If you are using Forms Authentication you need to set your forms and machinekey sections in web.config to be identical.

Here is a good link -> Forms Authentication Across Applications